1. Technical Field
The present disclosure relates to image processing, and more particularly to fusion of real-time 3D ultrasound volumes with C-arm CT reconstruction for improved visualization and navigation of catheters.
2. Discussion of Related Art
Pre- and intra-procedural cardiac imaging is an integral part of many cardiac interventions, both surgical and minimally invasive (e.g., percutaneous) ones. Regarding high-resolution static pre- and intra-operative imaging, Computed Tomography (CT), including rotational cone-beam CT (e.g., Siemens DynaCT) is widely used for diagnosis and planning. However these imaging modalities do not have real-time capabilities.
As real-time interventional modality, intra-cardiac echocardiography (ICE) is widely used in many catheterization laboratories, among others for guidance of transseptal catheterization and left atrial procedures. Siemens has recently developed an intra-cardiac ultrasound catheter, which is capable of acquiring real-time ultrasound volumes from within the heart. This novel imaging modality will by itself have an immense impact on intra-cardiac procedures. However, adequate training and experience are required in order to fully benefit from using ICE in routine EP procedures. A less trained or more occasional user will more likely have difficulties in finding the orientation of the ICE catheter within the body and recognize the anatomical structures, especially when the catheter moves quickly. Furthermore, for certain procedures, such as electrophysiological (EP) ablation for atrial fibrillation, fusion of such real-time 3D ICE data with pre-operative or intra-operative high resolution CT or MRI (Magnetic Resonance Imaging) imaging can provide better navigation and therefore reduce procedure time as well as improve the treatment outcome.
In addition, one typical complication of RF ablation for atrial fibrillation is associated with the esophagus (e.g., stenosis due to RF burning of the tissue in the esophageal wall). While it may not be easy to image the esophagus precisely with the ICE technology, it is well represented on the high-resolution CT or MRI data.
Complementing local real-time 3D acquisitions from the ICE catheter with the global and high-resolution map of the anatomy provided by the pre-operative or intra-operative imaging modality (CT or MRI) is yet another step to improve the usability of the ICE in targeting and navigation problems the physicians usually face during cardiac procedures.